Amateur video clips show the moment a plane crashes into several cars during the Shoreham airshow.

Seven people have been killed and a pilot has been left fighting for his life in hospital after a fighter jet taking part in an airshow crashed on to a busy A-road on Saturday afternoon.

Sussex police said the Hawker Hunter hit four cars on the A27 just north of Shoreham airport, where the Royal Air Forces Association airshow was being held.

The South East Coast Ambulance Service NHS Foundation Trust said seven people were declared dead at the scene, while the critically injured pilot was taken to the Royal Sussex County hospital in Brighton.

A further 14 people were treated for minor injuries. Unconfirmed reports said that two cyclists were killed in the crash. One of the vehicles hit was a Daimler regularly used for weddings.

The vintage Hawker Hunter single-seat fighter jet was attempting a loop manoeuvre, but the plane reportedly failed to pull out. One eyewitness said that the pilot did not eject before the plane hit the ground. The wrecked plane came to rest in a bush.

The Hawker Hunter was listed in the airshow programme as being flown by former RAF Harrier pilot Andy “Hilz” Hill, whose day job is as an Airbus captain for a major airline. Hill, who is well known for his aerobatic and airshow display work, is described by those in the industry as “a very experienced formation instructor and display pilot”.

Drivers on the A27 at the time of the incident tweeted pictures of the scene:

Dom Lawson was driving on the A27 when the jet crashed. “If I’d been 20 seconds faster I would not be having this conversation,” he said. He described how the plane passed just a few metres above his car with a deafening roar before slamming into the ground in a fireball just five or six vehicles in front. “It was like something out of Die Hard,” he added.

Lawson said he saw at least two cars on fire but added the incident could have been much worse if traffic lights at a nearby junction had not been at red.

Lucy Pearce, head of content at the Brighton Argus, was at the airshow. “All of a sudden there were all these gasps and screams and everyone jumped up. Then there was masses of smoke,” she told the newspaper.

Thousands of spectators were unable to leave the airport because the A27 was closed. Drivers on the road at the time of the accident tweeted pictures of the scene.

Organisers of the Shoreham airshow tweeted: “There has been a major incident outside the airfield boundary. The emergency services are responding. Updates will follow when available.”

Onlookers watch as a giant plume of smoke rises into the air following a plane crash at Shoreham airshow.

An Air Accidents Investigation Branch spokesman said it would be deploying a team to investigate.

Laura Raymond, a presenter for the local Splash FM radio station, said that a “couple of planes” were taking part in a jet display when one appeared to fly too close to the ground before onlookers saw a “huge ball of fire and black smoke”.

She told Sky News: “The Hawker Hunter T-7 display was under way. Within seconds we were thinking, ‘Gosh, that plane is going rather low.’ There was a ball of fire: we didn’t even hear an impact, and then plumes of black smoke.”

David Bryson, who was watching the airshow from Mill Hill, north of the airfield, said: “It was shocking – an awful thing to see. The plane was flying low, as is typical for an airshow.

“The pilot pulled up to do a loop and as he came down and pulled up to recover the loop it became obvious he wouldn’t manage to recover it. The jet pulled to the right and hit the road near the traffic lights. The plane was intact when it hit the ground but it then exploded. It was awful.”

Tina Tilley, chief executive of Worthing and Adur chamber of commerce, saw the crash from the VIP area at the show. “From where we were, we could see the jet came down very low and looked like it was going to scoop up – but it didn’t.

“There were flames and we knew it was right on the A27. Everyone was horrified and there were people crying. It’s horrendously sad for the families of everyone involved.”

Shoreham resident Dave Penwarden, 51, said he saw the plane explode in a “massive fireball”.

“The plane was coming out of a loop-the-loop, it was fairly low,” he said. “It just didn’t seem to have enough speed to come out of the loop, instead of powering out, it dropped too fast and hit the ground.

“There was a massive fireball and an awful lot of smoke. Afterwards there was a stunned silence. Everyone just went quiet.”